1. Field of the Present Invention
The present invention relates generally to food information monitoring systems, and, in particular, to methods of facilitating communication between sensor units, stationed in a plurality of remote locations for detecting temperature and other food data in a food service facility, and a central monitoring station for analysis and review.
2. Background
A wide variety of food service facilities, such as food service operators, grocery stores, university kitchens, banquet halls, food manufacturers and the like, utilize various types of food storage, handling and preparation apparatuses and containers in their operations. These apparatuses and containers, collectively referred to herein as food receptacles, may include means for heating or cooling the food contained therein, and may be stationary (such as a refrigerator) or portable (such as a serving cart). Examples of such devices include, but are not limited to, blast chillers, walk-in coolers and freezers as well as smaller coolers and freezers, ice machines, docked refrigerated trucks, mobile hot and cold food serving carts, table-top food warmers and coolers, ovens and cookers. If the temperature of the food contained in a particular food receptacle is important, then each such food receptacle must be monitored on at least a periodic basis to ensure that the temperatures remain within a particular range. Oftentimes, other food conditions must be monitored as well. The facilities are frequently quite large, and frequently make use of multiple food receptacles, thus making it difficult to carry out the monitoring operations by hand. For example, a typical facility may have a main kitchen, food storage equipment, a cafeteria, banquet halls, service corridors, and the like, all of which may have food in various stages of storage or preparation. It may also be necessary to monitor the location of the food receptacles within the facility. Thus, a need has developed for a centralized food information monitoring system.
A variety of food and temperature monitoring systems have been proposed to address this need. For example, U.S. Pat. Nos. 5,900,801 and 5,939,974 to Heagle et al. disclose a universal system for monitoring and controlling remote site systems at a plurality of individual food service facilities. Each remote site system includes a network and a plurality of temperature sensors associated with refrigerators, freezers and the like. The sensors are wired into the network. Each remote site system may also may include a plurality of individual sensors and other devices, including temperature sensors, which are not associated with particular equipment or designated work stations.
U.S. Pat. No. 5,951,900 to Smrke discloses an automatic temperature measurement-based control device for a cooking pot which may use wireless technology to transmit temperature information to a central unit. The central unit may likewise use wireless technology to communicate with a central electronic unit which in turn communicates with a controller for controlling the power or heat source for the pot. A system may incorporate more than one pot, temperature sensing device, heat source transceiver, controller, and/or heat source.
U.S. Pat. No. 6,213,404 to Dushane et al. discloses a design for a wireless, battery-operated temperature sensing device for transmitting sensed temperature information to a programmable thermostat. The temperature sensing device transmits information only periodically, and thus the device is capable of operating on the same inexpensive set of batteries for a period of months or even years. A plurality of such devices may be used to collect and transmit temperature information from particular apparatuses or locations to corresponding thermostats, or to a single thermostat.
U.S. Pat. No. 4,482,785 to Finnegan et al. discloses a refrigeration monitor system for monitoring an unattended freezer installation having a number of separate freezer compartments. The monitor system includes a network of temperature sensors arranged in the freezer compartments and connected to a common control. The connection between the sensor network and the common control may be completed using a wireless communication link.
U.S. Pat. No. 5,407,129 to Carey et al. discloses a system for monitoring the temperature and other environmental data in a poultry house and controlling temperature, etc. accordingly. The system includes a plurality of temperature sensors disposed around the interior of the poultry house. The sensors are in communication with a controller.
Finally, U.S. Pat. No. 5,460,006 to Torimitsu discloses a system for contemporaneously monitoring a variety of food storage apparatuses. U.S. Pat. No. 5,586,446 to Torimitsu discloses a system for monitoring a large number of ice making machines. U.S. Pat. No. 5,946,922 to Viard et al. discloses a system for collecting information about the operation of actual operation of food processing apparatus in a food processing plant.
Known remote food monitoring systems all suffer from a variety of significant problems. For example, one problem facing prior art food condition monitoring systems is that each known system is adapted for use in a wired environment (i.e., an environment in which the data collection portion of the system is physically connected directly to the central monitoring portion of the system) or a wireless environment, but not both. Although it has been recognized that certain systems, such as those disclosed in U.S. Pat. Nos. 5,951,900 and 4,482,785, may be produced in either wired or wireless versions, no single prior art system has been disclosed that is adaptable to either environment. Unfortunately, systems having only a single mode of communication have a number of limitations not recognized in the prior art. For example, it is often desirable for food information monitoring systems to make use of previously-existing local area networks and computers. Such networks sometimes include wireless access points for making wireless connections thereto, and sometimes do not. If a particular prior art monitoring system is to make use of one of these networks, the system must be tailored to the existing environment. Also, if a particular network is to be upgraded from a wired type to a wireless type by adding wireless access points, a corresponding conversion would be required in the components of prior art systems from a “wired” version to a “wireless” version. Thus, a need exists for a system capable of being used in either environment, while requiring little or no conversion process, and an improved method of installation based on the nature of an existing network.
Another problem with many prior art food condition monitoring systems is that they rely on the sensing devices to communicate data directly to the central collection apparatus. Wireless systems in particular are problematic because of the potential for data collisions as multiple sensing devices communicate back and forth with the central collection apparatus, and the necessity for sufficient transmission strength to ensure reliable communications, even when the sensing device is relatively distantly located from the central collection apparatus. Unfortunately, as the number of sensing devices in use in a particular food service facility increases, the propensity for data collisions increases dramatically. Further, strong transmission signals demand large amounts of power, thus either requiring the sensing devices to be “plugged in” or else severely limiting their battery life. Rather than confront the myriad issues raised by the use of wireless devices, many systems utilize dedicated wiring between each sensing device and the central collection apparatus.
Unfortunately, attempts to use some sort of intermediate unit that communicates with both the sensing devices and the central collection apparatus have shortcomings. For example, in the system of U.S. Pat. No. 5,951,900, temperature data is transmitted from a sensing device on the lid of a pan to an intermediate unit in the form of a controller and then wirelessly transmits control instructions from the controller to a heating unit, but this intermediate unit fails to relay the temperature data detected by the sensing device to the heating unit. In another example, U.S. Pat. No. 4,482,785 discloses a system in which sensing devices transmit detected temperature data to an intermediate unit which monitors the temperature data for alarm conditions and then wirelessly notifies a central apparatus when such an alarm condition exists, but fails to relay the temperature data itself. Thus, a need exists for an intermediate translator unit that relays temperature data from a plurality of sensing devices to a central collection apparatus, and particularly for a translator unit that receives data wirelessly from the sensing devices and relays the data wirelessly to the central collection apparatus.
As previously noted, it is often desirable for food information monitoring systems to make use of previously-existing local area networks and computers, because, among other factors, installing a new network, dedicated wires, wireless transceivers, and other equipment can be very expensive. Unfortunately, many food condition monitoring systems use proprietary or other non-standard communication protocols or the like, and are thus incapable of using existing equipment. Thus, a need exists for a system that is readily adaptable to standard wired and wireless network technology. Further, because Ethernets are already installed in so many food service facilities, a particular need exists for Ethernet-compatible food condition monitoring systems.
Another shortcoming of prior art temperature monitoring systems is their inability to handle more than one set of temperature data from any one sensor. In many situations, it is important to be able to remotely monitor more than one temperature associated with a single food, such as, for example, the ambient temperature surrounding the food as well as the core temperature of the food. Although a variety of temperature sensing devices are known that may be installed in a remote location to monitor a particular temperature characteristic and relay temperature data back to a central collection system, such sensing devices rely on only a single physical sensor. Further, the communication methodologies used to relay the sensed data back to the central collection system are not equipped to handle two different data sets. Unfortunately, the only way to remotely monitor two different temperatures with any known system is to install two separate remote sensors, which is prohibitively expensive and increases the complexity of the intra-system communications that must be carried out. Thus, a need exists for a system and method for monitoring more than one temperature characteristic in a particular location with a single remote unit.
Another problem with the remote units in prior art food monitoring systems is the inability to customize the settings of each remote unit based on the application for which it is to be used. In most systems, the remote sensor units are designed to be permanently installed in one location, and thus there is little need to update the settings for the sensor unit. However, in more sophisticated monitoring systems, and particularly in such systems where ease of installation is important, the ability to input application-specific data into the remote unit itself can be very important. Unfortunately, the few user interfaces includes with known sensor units are very limited in scope. For example, U.S. Pat. Nos. 5,900,801 and 5,939,974 each include a display for displaying detected measurements, but does not disclose the ability to input information about the particular situation in which the unit is to be used. Similarly, U.S. Pat. No. 6,213,404 discloses a method for a user to input an identifier for the sensor unit, but not for the food receptacle with which the sensor is to be used. Further, although handheld temperature sensing devices may have greater programmability, they unfortunately are not capable of being used in a remote real time monitoring context. Thus, a need exists for a food monitoring system that allows a user to input information about how a particular sensor unit is to be used directly into the sensor unit.
Similarly, it is also useful to facilitate the customization of a particular remote unit based on its intended use by presenting possible options to a user in the form of menus displayed in a built-in graphical interface in the remote unit. However, it may be necessary to change the menu options. Unfortunately, this may require the sensor unit to be reprogrammed or the like, which may be time-consuming or demand particular technical expertise. Thus, a need exists for a food monitoring system in which the menu options available through the various remote sensor units may be easily updated by downloading new options directly from the central computer of the monitoring system.
Another problem facing wireless remote food monitoring systems is the issue of how to handle sensed data when wireless communications are temporarily inoperative. Previous food information monitoring systems, such as the wireless system disclosed in U.S. Pat. No. 5,951,900 do not address this. Although handheld temperature sensing devices typically include a memory device that holds a large number of temperature measurements until the measurement data can be downloaded into a computer for review and analysis, but are unsuitable for use in a centralized monitoring environment. Thus, a need exists for a wireless food monitoring system that temporarily buffers detected food information until a wireless communication link may be reestablished.
Another issue facing remote food monitoring systems is how to manage the collection of data from multiple remote sensor units. U.S. Pat. Nos. 5,900,801 and 5,939,974 each disclose a system whereby a central unit polls various sensor units for their data, thereby controlling when each sensor unit transmits data and avoiding data collisions. However, this system uses wired connections between all sensor units and the central unit, thus making communications much simpler than they would be in a wireless environment. U.S. Pat. No. 5,951,900 discloses a wireless system in which two-way communications take place between a central unit and a sensor unit. However, the disclosed system appears to use only a very limited number of sensor units, thus simplifying the communication management needs of the system, and the patent does not disclose a methodology for controlling when the sensor units are to transmit data to the central unit. Thus, a need exists for a two-way wireless communications management system for a remote food monitoring system whereby individual sensor units may be polled for data under the control of a central computer.
Another shortcoming of existing remote food monitoring systems is their inability to track whether a particular remote unit in the system is currently active. Unfortunately, when the central computer of such a system is unaware that a particular remote unit is inactive, valuable time or processing capability may be wasted attempting to communicate with the sensor unit, and false alarms may even be generated by a false out-of-range temperature reading for the sensor. It may also be useful to provide a list of active and inactive remote sensor units to a user for planning purposes. Thus, a need exists for a remote food monitoring system capable of compiling a list of which remote units are active and which ones are not.
Another problem faced by known remote food monitoring systems is the difficulty inherent in organizing the data received from the various remote sensor units into a manageable format for review by a user. Sophisticated modern monitoring systems often utilize large numbers of sensor units located in multiple areas of a food service facility. Unfortunately, known prior art systems do not provide any means for grouping together sensor units sharing a common characteristic, such as being located in a particular area or room in the food service facility. As a result, a user usually needs to search through information pertaining to all sensor units in the system, which may be very time-consuming, especially if large numbers of sensor units are involved. Thus, a need exists for a way to group subsets of sensor units together to facilitate easier review and analysis by a user.
Another problem encountered by known remote food monitoring systems is that they are not typically intended to be used to monitor food in food receptacles that are regularly moved from place to place. As a result, they generally have no mechanism for automatically determining where a particular remote sensor unit is located at any given time. However, in food service facilities utilizing large numbers of sensor units or utilizing sensor units in a large area, it is often important for personnel to be able to physically check on a particular sensor unit quickly, and if the exact position of the sensor unit is not known, a considerably amount of time may be consumed in searching for the proper unit. U.S. Pat. No. 6,222,440 discloses a triangulation method for identifying a precise location of a particular sensor unit, but the method is extremely complex and requires highly specialized equipment. Thus, a need exists for a simple remote food monitoring system that automatically determines the location of each sensor unit in the system. Further, no system is known that permits a user to define a proper location for a particular sensor unit and then monitor the actual location of the sensor unit and alert the user when the sensor unit is in the wrong location. Thus, a particular need exists for a system capable of alerting a user when a sensor unit is in the wrong location.
Another shortcoming of known remote food monitoring systems is the lack of information such systems provide to a user about what is actually being monitored. Existing systems may provide the user with food temperature data itself, but fail to inform the user about the food being monitored, the food receptacle containing the food and the like. Instead, the user must typically manually track which sensor unit is monitoring which food and the like. Unfortunately, modern sophisticated applications demand greater detail than is available using other systems. Thus, a need exists for a remote food monitoring system that monitors a plurality of food receptacles and provides a user not only with data regarding the temperature of the food and the like, but also informs the user as to the type of food being monitored and the type of food receptacle that contains the food.
One important purpose of a remote food monitoring system is to alert users to the existence of a problem condition in a food or food receptacle being monitored as soon as possible. Known systems use a variety of means for alerting users. For example, U.S. Pat. No. 4,482,785 discloses the use of a telephone exchange to automatically dial a predetermined telephone number in the event of a temperature problem. Other systems use a variety of on-board alarm signals to alert a user to a problem. However, none of the prior art systems take are sophisticated enough to generate an alarm at both the sensor unit triggering the alarm and at a central monitoring station. Thus, a need exists for a system in which a sensor unit transmits temperature data to a central monitoring station for analysis, and when an out-of-bounds condition is encountered, the central monitoring station signals the remote sensor to generate an alarm signal in addition to an alarm being generated at the central monitoring station.
Another problem facing existing remote food monitoring systems is the general inconvenience involved in setting a desired temperature range for each separate remote temperature sensor, the desired temperature range being defined as the range of suitable temperatures for a particular food. Such desired temperatures may be established by law or regulation, according to user preference, or the like. Known methods for setting temperature ranges are frequently awkward and time-consuming. Depending on the application in which the sensors are employed, every sensor in the system may use the same temperature range, in which case the range is rarely adjusted once it has been set the first time. However, if every sensor unit uses a different range, or if the range must frequently be changed, then the ease with which a particular range may be updated becomes significant. Thus, a need exists for an improved system and method for adjusting the desired temperature range of each sensor unit.